JP4760432B2 - Passenger vehicle protection protector and existing tunnel expansion method using this protector - Google Patents

Description

  The present invention relates to a protector for protecting a passing vehicle and an expansion method of an existing tunnel using the protector, and in particular, in the plane alignment, the center line of the existing tunnel and the center line of the new tunnel after the expansion and repair are in agreement It is suitable for use when it is necessary to move the protector for the protection of the passing vehicle to the side during the excavation work, and the protection of the passing vehicle can greatly shorten the construction period and reduce the construction cost. The present invention relates to a protector for a vehicle and an improvement technique for an expansion method of an existing tunnel using the protector.

  In general, when expanding an existing road tunnel while securing the traffic of the vehicle, a protector that forms a protective space in the tunnel mine is installed prior to the expanded excavation as a protective measure for the passing vehicle. After the dredging, the upper and side of the installed protector will be enlarged and formed while performing tunnel excavation using the construction space.

  The protector is placed on the road surface and covers the upper side and the side of the protector, so that the inside is formed as a protective space for passing the vehicle. As shown in FIG. Then, a large number of these are connected and installed to form a desired length. The element 2a has a U-shape in which the lower part is opened in the cross-sectional shape, and is supported along a pair of surface plate materials 4 made of H-type steel material, and is also made of support material 6 and girder material made of H-type steel material. 8 are arranged in a straight line at appropriate intervals and fixed, and on the outside thereof, a side wall plate 10a made of a steel sheet pile or the like that forms an outline of the side wall portion 10 and a steel plate or the like are formed. It is formed by attaching the top plate 12. Further, a brace material 14 for reinforcement is provided between the struts 6 and 6 aligned in the longitudinal direction and between the beams 8. And the protector 2 formed by connecting and installing many elements 2a as mentioned above is normally provided in the existing tunnel over the full length (refer below, patent document 1 grade | etc.,).

  By the way, when expanding the existing tunnel, due to various constraints such as the influence on topography and nearby structures, the planar alignment of the new tunnel after the expansion is established as shown in FIG. The plane alignment of the tunnel B cannot be matched with the plane alignment of the tunnel, and the center alignment b of the existing tunnel B intersects with the center alignment a of the new tunnel A after the enlargement formation. There is. In such a case, the cross-sectional shape of the excavation target ground portion for enlarging the tunnel cross-section changes along the longitudinal direction of the tunnel.

  In other words, in this illustrated example, the existing tunnel B and the new tunnel A have the left road surface ends coincident with each other when viewed from the excavation direction at the wellhead on the construction start side, and the cross-sectional shape of the ground C to be excavated Is similar to a crescent shape where the right side is thicker and the left side thinner. On the other hand, the road surface ends on the right side from the excavation direction are coincident with each other at the end of the construction side, and the cross-sectional shape of the ground C to be excavated is opposite to the starting side, but the right side is thin and the left side is thick crescent. It is similar to. Further, in the vicinity of the center of the tunnel length where the two center lines a and b intersect, the cross-sectional shape of the excavation target ground C is similar to a crescent shape whose thickness is almost symmetrical and equal. . When the two tunnels A and B are in such a positional relationship, the horizontal cross-sectional shape of the excavation target ground C has a triangular shape in which the thickness gradually increases on one side wall side, and the other side wall side Then, it has a triangular shape with a gradually decreasing thickness.

  Then, when excavating the excavation target ground C having such a shape, if the protector 2 for protecting a passing vehicle is installed in the existing tunnel B, the excavation target ground C crosses the excavation ground at the starting point side. The excavating machine interferes with the protector 2 on the side of the side wall where the surface is thin, making it difficult or impossible to excavate without securing a space necessary for excavation work. .

  For this reason, in such a conventional case, excavation has been performed by an enforcement method as shown in FIGS. 3 (a) and 3 (b). That is, as a first step, first, the excavation target ground Ca of the part that is exposed with a large thickness in the cross section at the wellhead on the starting side of the excavation work and can sufficiently secure a space above a certain level necessary for the excavation work is first obtained. Primary excavation. As this excavation progresses, the thickness of the cross section gradually decreases along with this, and it becomes impossible to secure a sufficient space. At this point, the primary excavation is finished.

  Next, the protector element 2a installed over the length of the tunnel expanded on one side by the primary excavation is moved sideways toward the enlarged formation side, and the primary transfer is performed, and the opposite cross section is thin. A sufficient excavation work space is ensured between the side wall portion and the protector element 2a. After dredging, the excavation target ground Cb having a thin cross-section that can be excavated is secondarily excavated from the wellhead on the starting side. As this excavation progresses, the thickness of the cross section continues to increase gradually, so that this secondary excavation can be carried out to the wellhead on the end point side.

After the completion of the secondary excavation, the excavation target ground Cc portion left unearthed during the primary excavation is tertiary excavated. Prior to this, in order to secure the excavation work space, the excavation target ground Cc portion is covered. The installed protector element 2a is moved in the direction expanded by the above-mentioned secondary excavation for secondary transfer.
JP 2001-123798 A

  By the way, when it is the expansion method of the existing tunnel using the above conventional protectors 2 for protecting a passing vehicle, the protector element 2a that is moved and the protector element that is not moved are moved when the protector element 2a is temporarily moved sideways. The linear shape is bent at the connecting portion with 2a, and the adjacent protector elements 2a and 2a are separated from each other at the portion. Therefore, in order to protect the bent portion and connect the alignment gently, it is necessary to interpose a dedicated protector element 2b in the connection portion. In order to carry the protector element 2b dedicated to the bent portion into the tunnel B, it is necessary to carry out all of the many protector element 2a groups to be temporarily moved out of the tunnel B once.

  Therefore, in the construction method using the conventional protector 2 for protecting a passing vehicle, a great deal of labor and time are spent when the protector element 2a is moved, leading to a longer construction period and a higher construction cost. There was a problem of ending up.

  The present invention has been made in view of the above-mentioned problems, and the purpose of the excavation is that the center line of the existing tunnel does not coincide with the center line of the new tunnel after the enlargement / renovation in the plane alignment, and the excavation thereof is performed. A protector for protecting the passing vehicle, which can be used for cases where it is essential to move the protector for protecting the passing vehicle to the side during the work, and which can greatly shorten the construction period and reduce the construction cost, and use this protector. The purpose is to provide an expansion method for existing tunnels.

  In order to achieve the above object, in the protector for protecting a passing vehicle according to the present invention, a protector element having a predetermined length of a U-shaped cross section with a lower side formed by a side wall and a top plate is opened on the road surface. In a protector for protecting a passing vehicle that is mounted and connected many in the front and rear, and forms a protection space for passing a vehicle inside and covering the upper side and the side, at the four corners of the lower ends of both side walls of the protector element, Provided with a moving mechanism that supports the protector element so as to be laterally movable, both side wall portions of the protector element connected to the front and back are connected by a connecting portion protection side plate that has a hinge portion and can be bent. The connecting part protection side plate is provided with a distance adjusting means capable of absorbing and adjusting the distance between the side walls of the front and rear protector elements, and at the upper part of the connecting part between the protector elements. The top plate of one of the protector element and fixed at one end, and providing a connecting portion protective top plate overmolded by edge cutting the other end against the top plate portion of the other of the protector element.

  Here, the moving mechanism is a biaxial jack in which a lifting jack that expands and contracts in the vertical direction and a horizontal moving jack that expands and contracts in the horizontal direction are integrated, and the biaxial jack includes the protector element. It is attached to the lower surface of the support stay that protrudes outward from the lower end of the side wall portion of the support wall so as to be relatively slidable through a sliding plate, and extends downward from the protruding end of the support stay. The horizontal movement jack is connected to the engaged bracket, and the lower surface of the support stay has a height dimension from the lower end surface that contacts the road surface of the protector element. A configuration in which the size is set to be larger than the size can be achieved.

  Further, a sensor for detecting the expansion / contraction operation amount of each horizontal movement jack, an operation amount adjustment means for adjusting the expansion / contraction operation amount, and a control means for controlling the operation of each operation amount adjustment means are provided, The control means, when moving each protector element installed along the plane linear line of the current setting sideways along the predetermined plane linear line of the new setting, controls the plane in the current setting of each protector element. The amount of lateral movement from the linear line to the newly set plane linear line is calculated by the amount of movement of each protector element for each horizontal movement jack, and the amount of movement is calculated. Four horizontal movement jacks, each of which has an expansion / contraction operation control amount of each horizontal movement jack and is disposed in an adjacent protector element across the connecting portion and approximates the expansion / contraction operation control amount. They are made the same control target group and are grouped individually for each connecting part, and the two horizontal movement jacks arranged at the foremost end of the many connected protector elements and having the same amount of expansion / contraction operation control and the last Two horizontal movement jacks arranged at the ends and having the same amount of expansion / contraction operation control are individually grouped into the same control target group, and the expansion / contraction speed and the operation timing for each control target group are respectively It is also possible to adopt a configuration in which the operation is controlled with a difference corresponding to the mutual relationship between the expansion and contraction operation control amounts of the two.

  In addition, the moving mechanism includes a traveling drive unit capable of self-propelling on a road surface, and a lift jack that is provided integrally with the traveling drive unit and expands and contracts in the vertical direction, and the side wall portion of the protector element. The lift jack may be swingably attached to the lower surface of the support stay that is provided integrally with the lower end so as to protrude outward.

  On the other hand, as an invention of an expansion method for an existing tunnel, the above-mentioned protector for protecting the passing vehicle is installed in the existing tunnel in the expansion of the existing tunnel where the plane alignment of the existing tunnel does not match the plane alignment of the new tunnel after expansion and renovation. An expansion method for an existing tunnel that is installed in a vehicle and secures the traffic of the vehicle while expanding the existing tunnel, and each protector element is arranged and connected in the existing tunnel to install a vehicle traffic protection protector. A primary excavation step in which a ground excavation work space is secured around the vehicle traffic protection protector at the excavation start side wellhead from the excavation start side wellhead, and the primary excavation After the completion of the process, the vehicle traffic protection protector element at the enlarged formation site is moved toward the enlarged formation direction side by the primary excavation. A secondary excavation for excavating a ground part where excavation work space is secured around the vehicle traffic protection protector from the excavation origin side wellhead side after the transfer process is completed. Each of the steps, and if necessary, the transfer step and the subsequent excavation step are sequentially repeated after dredging.

  According to the protector for protecting a passing vehicle of the present invention having the above-described configuration, between the protector elements connected to the front and rear, both side wall portions are connected to each other by a connecting portion protection side plate that has a hinge portion and can be bent. The connecting part protection side plate is provided with a distance adjusting means capable of absorbing and adjusting the distance between the side walls of the front and rear protector elements, and the connecting part between the top plate parts of the protector element includes There is a connecting part protection top plate that is fixed to the top plate part of the protector element, and the other end is cut off and covered by the top plate part of the other protector element. It is possible to flexibly connect the front and rear protector elements while ensuring the flexibility. And since the movement mechanism which supports this protector element so that movement to the right and left is possible at the four corners of the both-sides wall part lower end of a protector element, each element is easily carried out to the side using the said move mechanism. In addition, changes in the relative position such as the separation distance and angle of the front and rear elements that occur during the movement can be absorbed by the connecting portion. For this reason, when the protector for protecting a passing vehicle with a large number of elements connected is moved to the side, it can be smoothly turned around and the labor and time spent at the time of the transfer can be reduced. And the traffic closure caused by turning the protector can be reduced as quickly as possible.

  Further, by adopting a horizontal movement jack in the moving mechanism, the four horizontal movement jack groups arranged in the vicinity of each connecting portion are made the same independent control target group, and the front end of the protector The two horizontal movement jack groups and the last horizontal movement jack group are also grouped into independent control target groups, and the expansion / contraction speed and the operation timing of each control target group are controlled individually. The operation control is performed collectively with a difference corresponding to the mutual relationship of the amount of expansion / contraction operation control between the target groups, and the control means includes the data of the plane linear line of the current setting before the relocation of the protector and the relocation If the data of the plane linear line is input and stored in advance, the horizontal movement for each control target group based on the data of the two plane linear lines The expansion operation control amount of the jacks by automatically calculated, it is possible to smoothly and quickly automatically perform relocation of the protector.

  Further, according to the existing tunnel expansion method using the vehicle protection device according to the present invention, the transfer of the vehicle protection protector to the side can be smoothly performed in the mine without carrying the protector element out of the tunnel. Therefore, regardless of the amount of misalignment that occurs in the plane alignment between the existing tunnel and the new tunnel after the expansion, the protector for the protection of passing vehicles can be installed within the tunnel portion of the expanded excavation site. The transfer to the side can be easily performed to secure a desired construction space above a certain level, thereby enabling efficient construction. In addition, since a large construction machine that matches the secured construction space can be used, the construction speed can be increased and the construction period can be shortened as much as possible.

  Hereinafter, an example of a preferred embodiment of a protector for protecting a passing vehicle according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 4A is a front view of a protector element, which is a minimum unit constituting the protector for protecting a passing vehicle according to the present embodiment. The protector element 20a is placed on the road surface, and a large number of the protector elements 20a are connected to the front and rear. Thus, the vehicle protection protector 20 that defines a vehicle traffic protection space covering the upper side and the side is formed. Here, since the basic configuration of the main body itself of the protector element 20a is formed in the same manner as the conventional one shown in FIG. 1, the same reference numerals are given to the same members, and the description thereof is omitted. .

  The protector element 20a is provided with a moving mechanism 22 that supports the protector element 20a so that the protector element 20a can be moved laterally at the four corners at the lower ends of the left and right side walls. In this embodiment, as shown in FIG. 4B, the moving mechanism 22 is integrated with a lift jack 24 that expands and contracts in the vertical direction and a horizontal movement jack 26 that expands and contracts in the horizontal direction. A two-axis jack 28 is employed. The biaxial jack 28 is slid relative to the lower surface of a support stay 30 integrally provided by protruding outward from the lower end of the side wall 10 of the protector element 20a via a sliding plate 32. The horizontal movement jack 26 is connected to the expansion / contraction movement side of an engagement bracket 34 that is movably attached and integrally extends downward from the protruding end of the support stay 30. .

  The lower surface of the support stay 30 is provided at the lower end portion of the protector element 20a so that the height dimension from the lower end surface of the surface plate material 4 that contacts the road surface is higher than the height dimension when the lift jack 24 is shortened. The lifting jack 24 is separated from the road surface when shortened, and when it is extended, it contacts the road surface and lifts the protector element 20a upward to float. Then, by operating the horizontal movement jack 26 in this lifted state, the body portion of the protector element 20a supported by the lift jack 24 via the sliding plate can be moved toward the side in the longitudinal direction. It has become. Here, the reaction force at the time of horizontal movement to the side is taken from the road surface via the lifting jack 24. Since the lift jack 24 bears the load of the protector element 20a, the reaction force of the horizontal movement force can be sufficiently obtained by the frictional force with the road surface.

  FIG. 5A is a side view of the two protector elements 20a and 20a connected to the front and rear, and FIG. 5B is an enlarged view of the connecting portion, and the distance adjusting means provided in the connecting portion is shortened. FIG. 8C is a diagram showing a state where the separation distance adjusting means is extended. As shown in the figure, the protector elements 20a, 20a connected in the front-rear direction are connected to each other by a connecting portion protection side plate 36 made of a steel plate having a pair of left and right side wall portions 10, 10 having a hinge portion 36a. It is connected to. The connecting portion protection side plate 36 is fixed to the side wall portion 10 of the protector element 20a by being fixed to the fixed side protection side plate 38, and is fixed to the fixed side protection side plate 38 through a long hole 39a and a stud bolt 39b. A separation distance adjustment means that can be adjusted to absorb the separation distance between the side wall portions 10, 10 of the front and rear protector elements 20a, 20a is composed of a separation distance adjustment side protection side plate 40 that is movably joined. . In the illustrated example, a stud bolt 39b is erected on the fixed-side protection plate 38, and a horizontally long slot 39a through which the stud bolt 39b is inserted is formed in the separation distance adjustment-side protection side plate 40. Further, a hinge part 36 a is provided on the separation distance adjustment side protection side plate 40. Here, in a normal state, a nut that is screwed into the stud bolt 39b is tightened, and the fixed side protection side plate 38 and the separation distance adjustment side protection side plate 40 are firmly fastened and integrated, and the protector element 20a, The nut is loosened during the lateral movement of 20a, so that the change in the separation distance caused by the movement can be absorbed.

  FIG. 6 is a plan view showing two protector elements 20a, 20a connected in the front-rear direction, and shows a relatively bent state. As shown in the figure, one end of the protector element 20a (on the left side shown in the figure) is firmly fixed to the top plate 12 of the protector element 20a, 20a by welding 41 or the like, and the other end Is provided with a connecting portion protection top plate 42 that is edge-cut and covered by the top plate portion 12 of the other protector element 20a (right side in the drawing). And this connection part protection top plate 42 is formed wider than the lateral width of the said protector element 20a, 20a. Although not shown in the drawing, the left and right ends of the connecting portion protection top plate 42 are bent downward and are suspended for a predetermined length. Further, a sliding plate for smooth sliding with the connecting portion protection top plate 42 is provided on the top plate portion of the protection element on the side cut off from the connecting portion protection top plate 42. It is preferable to do this.

  FIG. 7 is a diagram showing an example of a control system in the case of automatically controlling the operation using a hydraulic jack 26 for horizontal movement as the moving mechanism 22. As shown in the figure, this control system includes a sensor 46 that is attached to each horizontal movement jack 26 and detects the amount of expansion / contraction operation, an operation amount adjustment means 48 that adjusts the amount of expansion / contraction operation, and each operation amount adjustment. Control means 50 for controlling the operation of the means 48 is provided.

  The operation amount adjusting means 48 is a control valve provided in the middle of a hydraulic line 54 that guides the high-pressure hydraulic oil delivered from the hydraulic pump 52 to each horizontal movement jack 26, and the control means 50 is a control panel incorporating a computer. It becomes. Information on the actual expansion / contraction operation amount detected by the sensor 46 is input to the control panel 50, and the position data of the protector elements 20a, 20a,... .. And information on position data on a newly set planar linear line that is the destination of movement of each protector element 20a, 20a,... Are preliminarily input and stored. The operation of the pump 52 and the operation of the control valve 48 are controlled.

  Here, the control panel 50 moves the protector elements 20a installed along the currently set planar linear line to the side along the predetermined new set linear linear line. , 20a,..., 20a,... The horizontal movement amount of the protector elements 20a, 20a,. The movement amount for each part is calculated, and the movement amount is set as the expansion / contraction operation control amount of each horizontal movement jack 26. In addition, the total of four horizontal movement jacks 26 arranged two by two on the protector elements 20a and 20a adjacent to each other with the coupling portion between them are approximated in their expansion / contraction operation control amounts. The control target group is divided into groups for each connection portion, and the operation control is performed by one control valve 48 for each control target group unit. Similarly, in the protector 20 for protecting a passing vehicle, in which a large number of protector elements 20a, 20a,... Are connected, two horizontal movement jacks 26 arranged at the foremost end and having the same amount of expansion / contraction operation control and the last The two horizontal movement jacks 26 arranged at the ends and having the same expansion / contraction operation control amount are also grouped individually as the same control target group, and one control valve 48 is provided for each control target group unit. The operation control is performed at

  Then, the control panel 50 controls the expansion / contraction speed and the operation timing of each control target group with a difference corresponding to the magnitude of the expansion / contraction operation amount between the groups. That is, as the operation control pattern, (1) the group having a larger expansion / contraction operation control amount makes the expansion / contraction speed faster so that the operation times of all jacks 26 are equalized. (2) While the expansion / contraction speed is uniform, For nail loops with a larger amount of expansion / contraction operation control, the start timing of the expansion / contraction operation is advanced to align the operation end timing of all jacks 26. (3) Difference from the amount of expansion / contraction operation control between adjacent control target groups In addition to keeping the value within a certain value, various variations are conceivable.

  FIG. 8 is a flowchart schematically showing an example of the flow of control contents by the control panel 50 as control means. As shown in the figure, in this example, when the control is started, first, the position data of each protector element 20a, 20a, 20a,... S10). Next, each protector element 20a, 20a,... Is read in position data on a newly set planar linear line to be moved (S20). Based on the read data, the movement amount of each protector element 20a, 20a,... For each horizontal movement jack 26 is calculated as the expansion / contraction operation control amount of each horizontal movement jack 26 (S30). ). Then, the expansion / contraction operation control amount of the four horizontal movement jacks 26 adjacent to each other with the connecting portion being the same control target group is determined for each control target group (S40). The two horizontal movement jacks 26 arranged at the foremost end and having the same expansion / contraction operation control amount are set as the same control target group, and the expansion / contraction operation control amount is determined. The expansion / contraction operation amounts of the two horizontal movement jacks 26 arranged at the foremost end that are equally controlled by the same control target group are determined (S50). Similarly, the expansion / contraction operation control amounts of the two horizontal movement jacks 26 arranged at the rearmost end having the same expansion / contraction operation control amount in the same control target group are determined (S60). The actual expansion / contraction operation amount of each horizontal movement jack 26 is detected by an input signal from the sensor (S70).

  Next, the expansion / contraction speed of the horizontal movement jacks 26 for each control target group and the operation timing thereof are determined while giving a difference corresponding to the mutual relationship of the magnitude of the expansion / contraction operation control amount between the control target groups. Then, the operation amount adjusting means 48 is feedback-controlled based on the actual expansion / contraction operation amount of each horizontal movement jack 26 (S80). Thereafter, all the horizontal movement jacks 26 are expanded and contracted to a stroke corresponding to the determined expansion / contraction operation control amount, and it is determined whether the expansion / contraction operation is completed in all the jacks 26 (S90). And when the said determination is No, it returns to S70, loops control, and complete | finishes control when the said determination becomes Yes.

  9 to 11 are diagrams for explaining an expansion method of the existing tunnel B using the protector 20 for protecting a passing vehicle according to the present invention. The horizontal alignment of the existing tunnel B and the new alignment of the tunnel A after the expansion and repair are described. FIG. 9 is a cross-sectional view showing an initial stage after installation of a protector for protecting a passing vehicle, FIG. FIG. 11 is a cross-sectional view showing a state in which the protector for protecting the passing vehicle is moved sideways after the end of the primary excavation, and FIG. 11 shows a state in which the protector for protecting the passing vehicle is moved secondary to the side after the end of the secondary excavation. It is sectional drawing.

  Here, in the illustrated example, the center line b of the existing tunnel B and the center line a of the new tunnel A are equal to the length of the tunnel, as in the description in FIG. 2 described in the background art. Crossing near the center, the existing tunnel B and the new tunnel A have the left road surface ends coincide with each other at the wellhead on the construction start side, and the cross-sectional shape of the excavation target ground C is thick on the right side. The left side is thin and resembles a crescent shape with a gradually decreasing thickness. On the other hand, the road surface ends on the right side coincide with each other when viewed from the excavation direction at the end of the construction side, and the cross-sectional shape of the excavation target ground C is thin on the right side and thick on the left side as opposed to the starting side. It is similar to the crescent shape. In the vicinity of the center of the tunnel length where the two center lines a and b intersect, the cross-sectional shape of the excavation target ground C is similar to a crescent shape whose thickness is almost symmetrical and equal. When the two tunnels A and B are in such a positional relationship, the horizontal cross-sectional shape of the excavation target ground C has a triangular shape in which the thickness gradually increases on one side wall side, and the other side wall side Then, it has a triangular shape with a gradually decreasing thickness.

  And, when excavating the excavation target ground C having the shape as described above, in the expansion method of the existing tunnel according to the present invention, construction is performed according to the following procedure. That is, as shown in FIG. 9, first, there is a step of installing the protector 20 for protecting vehicle traffic by arranging and connecting a large number of protector elements 20a, 20a,... Done. Here, the side wall portion to be brought into proximity is a side wall portion in which the thickness of the cross section of the excavation target ground C is thin on the starting side wellhead side. Thus, when the vehicle traffic protection protector 20 is installed in the vicinity of one side wall of the existing excavation target ground C, the space between the expanded excavation target ground on the other side wall and the protector element 20a is made as much as possible. Therefore, the excavation work space is widened, which leads to improvement in workability.

  Next, a primary excavation process is performed in which the excavation target ground Ca is excavated from the excavation starting point side pit of the ground portion where the excavation work space around the vehicle traffic protection protector 20 is secured. Then, after the primary excavation process is finished, the primary transfer process of moving the elements 20a, 20a,... Of the vehicle traffic protection protector 20 at the enlarged formation part to the side toward the enlarged formation direction side by the primary excavation. I do.

  In addition, after the primary relocation process is completed, a secondary excavation process is performed in which the excavation target ground Cb is excavated from the excavation starting point side entrance where the excavation work space around the vehicle traffic protection protector 20 is secured. . After dredging, the above relocation process and the subsequent excavation process are repeated as necessary. In this embodiment, after completion of the secondary excavation process, the elements 20a, 20a,... Of the vehicle traffic protection protector 20 at the enlarged formation portion are directed toward the center line side of the planar alignment of the new tunnel after the enlarged formation. A secondary relocation process is performed to move sideways, and after this secondary relocation process is completed, the ground to be excavated in the ground portion where the excavation work space around the vehicle traffic protection protector 20 is secured from the excavation origin side wellhead. The third excavation process for excavating Cc is performed.

  That is, each process from the protector installation process to the tertiary excavation process itself is substantially the same as the conventional method, and there is no significant difference. However, the vehicle traffic protection protector 20 employed in the construction method of the present invention is remarkably different from the conventional one, and the protector 20 formed by connecting a number of elements 20a, 20a,. It is possible to smoothly perform the cutting operation, and it is not necessary to carry out the elements 20a, 20a,. Therefore, it is possible to save as much as possible the labor and time spent at the time of the relocation, and to reduce the traffic closure accompanying the turning of the protector 20 as quickly as possible. become. In addition, since the transfer to the side can be carried out smoothly and in a short time in the tunnel mine, regardless of the size of the plane linear displacement generated between the existing tunnel B and the new tunnel A after the enlargement, the enlarged excavation In the tunnel part after formation, the moving vehicle protection protector 20 can be easily moved to the side, so that a desired construction space of a certain level or more can be secured, thereby enabling efficient construction. In addition, since a large construction machine can be used according to the secured construction space, the construction speed can be increased and the construction period can be shortened as much as possible.

  In the protector element 20a described above, an example in which the two-shaft hydraulic jack 28 is used for the moving mechanism 22 is shown, but the present invention is not limited to this, and various types of moving mechanism 22 can be adopted. For example, although not shown, a protector element 20a is adopted that includes a travel drive unit capable of self-propelling on a road surface and a lift jack that is provided integrally with the travel drive unit and expands and contracts in the vertical direction. The tip of the lift jack may be attached to the lower surface of the support stay 30 integrally provided so as to protrude outward from the lower end of the side wall portion through a rotating disk.

It is a perspective view of the protector element main-body part common to the past and this invention. It is sectional drawing for demonstrating the example in the case where the centerline of the existing tunnel and the centerline of the tunnel after expansion modification do not correspond in plane alignment, but cross | intersect. It is a plane sectional view explaining the expansion method of the existing tunnel at the time of using the protector for the conventional passing vehicles protection. (A) is a front view which shows one Example of the protector element used as the minimum structural unit of the protector for a traffic vehicle which concerns on this invention, (b) is a biaxial type provided as a moving mechanism in the lower end part of a protector element It is a side view which shows an example of a jack. (A) is a side view of two protector elements connected back and forth, (b) is a diagram showing a state in which the separation distance adjusting means provided in the connection portion is shortened, and (c) is the separation distance. It is a figure which shows the state by which the adjustment means was expanded. It is a top view of two protector elements connected back and forth, and shows the bent state. It is a figure which shows an example of the control means in the case of controlling automatically the action | operation using the hydraulic type jack for the horizontal movement as a moving mechanism. It is a flowchart which shows roughly an example of the flow of the control content by a control means. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which demonstrates the expansion method of the existing tunnel using the protector for a traffic vehicle protection which concerns on this invention, and shows the initial stage after installation of the protector for a traffic vehicle protection. It is sectional drawing which shows the state which moved the protector for the protection of a passing vehicle primary sideward after completion | finish of primary excavation same as the above. It is sectional drawing which shows the state which carried out the secondary transfer of the protector for a passing vehicle protection to the side after completion | finish of secondary excavation same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Side wall part 12 Top plate part 20 Passing vehicle protection protector 20a Protector element 22 Movement mechanism 24 Lift jack 26 Horizontal movement jack 28 Two axis jack 30 Support stay 32 Sliding plate 34 Engagement bracket 36 Connection part protection side plate 36a Hinge 38 Fixed side protection side plate 39a Slot (separation distance adjusting means)
39b Stud bolt (separation distance adjusting means)
40 Separation distance adjustment side protection side plate 42 Connection part protection top plate 46 Sensor 48 Operating amount adjustment means (control valve)
50 Control means (control panel)
52 Hydraulic pump A New tunnel B Existing tunnel C Ground to be excavated

Claims (5)

A vehicle in which a protector element having a predetermined U-shaped cross-section with a side wall and a top plate that is open at the bottom is placed on the road surface and connected to the front and back, and the upper and sides are covered inside. A vehicle protection protector that forms a protective space for traffic,
At the four corners at the lower ends of both side wall portions of the protector element, there are provided moving mechanisms for supporting the protector element so as to be movable laterally,
Both side walls of the protector element connected to the front and rear are connected to each other by a connecting part protection side plate which has a hinge part and can be bent, and the side wall part of the front and rear protector elements is connected to the connection part protection side plate. A separation distance adjusting means capable of absorbing the separation distance between each other is provided,
In addition, at the upper part of the connecting portion between the protector elements, there is a connecting portion protective top plate that is fixed to the top plate portion of one protector element and whose other end is cut off and covered by the top plate portion of the other protector element. Provided,
A protector for protecting a passing vehicle. The moving mechanism is a biaxial jack in which a lifting jack that expands and contracts in the vertical direction and a horizontal moving jack that expands and contracts in the horizontal direction are integrated.
The biaxial jack is
The lift jack is attached to the lower surface of the support stay integrally provided so as to protrude outward from the lower end of the side wall of the protector element via a sliding plate, and can be relatively slidably moved.
The horizontal movement jack is provided connected to an engagement bracket formed integrally extending downward from the protruding end of the support stay,
The lower surface of the support stay is set such that the height dimension from the lower end surface that contacts the road surface of the protector element is larger than the height dimension when the lift jack is shortened.
The protector for a vehicle protection of Claim 1 characterized by the above-mentioned. A sensor for detecting the expansion / contraction operation amount of each horizontal movement jack, an operation amount adjustment means for adjusting the expansion / contraction operation amount, and a control means for controlling the operation of each operation amount adjustment means,
The control means is to move each protector element installed along the plane linear line of the current setting to the side along the plane linear line of the predetermined new setting.
The amount of movement of each protector element from the horizontal alignment line to the newly set horizontal alignment line in the current setting is determined by the movement amount of each protector element for each horizontal movement jack. Calculate the amount of movement as the amount of expansion / contraction operation control of each horizontal movement jack,
The four horizontal movement jacks which are arranged in the protector elements adjacent to each other with the connecting portion interposed therebetween and whose expansion / contraction operation control amount approximates to each other are grouped individually for each connecting portion as the same control target group. In addition, two horizontal movement jacks disposed at the foremost end of the connected protector elements and having the same amount of expansion / contraction operation control, and two horizontal movement jacks disposed at the rear end and having the same amount of expansion / contraction operation control. Individually grouped as the same control target group,
3. The vehicle protection according to claim 2, wherein the expansion / contraction speed and the operation timing of each control target group are controlled to operate with a difference corresponding to the correlation between the respective expansion / contraction operation control amounts. Protector. The moving mechanism has a traveling drive unit capable of self-propelling on a road surface, and a lift jack that is provided integrally with the traveling drive unit and expands and contracts in the vertical direction.
The tip of the lift jack is attached to the lower surface of the support stay integrally provided so as to protrude outward from the lower end of the side wall of the protector element via a rotating disk,
The protector for a vehicle protection of Claim 1 characterized by the above-mentioned. In the expansion construction of the existing tunnel where the plane alignment of the existing tunnel does not match the plane alignment of the new tunnel after expansion and renovation, the protector for protecting a passing vehicle according to any one of claims 1 to 4 is installed in the existing tunnel An expansion method for an existing tunnel that performs the expansion work of the existing tunnel while ensuring traffic of the vehicle,
A step of installing a protector for vehicle traffic protection by arranging and connecting each protector element in the existing tunnel; and
A primary excavation step of excavating a ground part in which an excavation work space is secured around the vehicle traffic protection protector from the excavation origin side wellhead at the excavation origin side wellhead;
After the primary excavation step is completed, a moving step of moving the element of the vehicle traffic protection protector in the enlarged formation portion toward the enlarged formation direction side by the primary excavation and moving it to the side;
A secondary excavation step of excavating a ground portion in which an excavation work space is secured around the vehicle traffic protection protector from the excavation start side wellhead side after the transfer step is completed;
A method for expanding an existing tunnel, comprising at least the steps described above, wherein the relocation step and the subsequent excavation step are sequentially repeated as necessary after dredging.

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